The Internet has been very successful in part because its decentralized control has permitted the rapid development and deployment of applications and services. The success of the Internet is demonstrated by the enormous traffic growth that has already made the Internet carry more traffic than the phone network [24,69,100,47].
If the Internet is based on packet switching, why would I want to use circuit switching? The answer is simple. There is a mismatch between the evolution rates of traffic and capacity of the Internet, and circuit switching can help bridge the gap between demand and supply.
The capacity of the network has to keep up with Internet traffic growth rates that are 10 times larger than that of voice traffic. Coffman and Odlyzko, among others, have been studying traffic growth in the Internet, and they have found that traffic has been doubling every year since 1997 [47,135]. Studies by RHK [162] and Papagiannaki et al. [140] indicate similar growth rates. The capacity of the Internet should match these growth rates in order to avoid the collapse of the network. The next section studies the evolution trends of the underlying technologies in a router, and, as we will see, router technology is being outpaced by Internet demand.
If routers cannot keep up with demand, then one can only expand the network capacity by adding more nodes and links. This not only requires more equipment, but also more central offices to house them. It is an expensive proposition, and it also creates a more complex network, making network planning and maintenance more difficult. This Thesis takes a different approach; it focuses on how to improve the performance of the existing network by increasing the capacity of switches and links with the use of circuit switching in the core of the network.